Compass



Dec. 26, 1944. ELGLBRQCKMAN $366,000

COMPASS 1 Filed Sept. 29, 1941 INVENT OR.

BY EELEREIBKMHN Patented Dec. 26, 1 944 UNITED STATES PATENT OFFICE COMPASS Edwin G. Brockman, Indianola, Iowa. Application September 29, 1941, Serial N 0.412393 4 Claims. (o1. 33-152) The principal object of this invention is to provide a relatively flat combination compass, ruler and protractor.

A further object of this invention is to provide a compass that may be easily carried in a book or in the vest pocket of the user.

A still further object of this invention is to provide a new and novel method of detachably and adjustably securing th lead in a compass. I

A still further object of my invention is to provide a combination compass, protractor and ruler that is economical in manufacture and durable in use.

These and other objects will be apparent to those skilled in the art.

My invention consists in the construction, arrangement and combination of the various parts of the device, whereby the objects contemplated are attained as hereinafter more fully set forth, pointed out in my claims and illustrated in the accompanying drawing, in which:

Fig. 1 is a side view of my device ready for use.

Fig. 2 is a side view of my device showing its other side.

Fig. 3 is an enlarged cross sectional view of my device taken on line 3--3 of Fig. 1.

Fig. 4 is an enlarged view of one of the ends of the compass that holds the lead and more fully illustrates its construction.

Fig. 5 is a top plan view of my compass.

Compasses are very old. The usual compass, however, has relatively large arms circular in cross section and with various protruding knobs and like. Such compasses cannot be easily or successfully carried in the pocket or placedand carried within the covers of a book without distorting anddamaging the book. I have overcome such objections by providing a simple and substantially flat compass.

Referring to the drawing, I have used the numerals I and II to designate the two arm portions of my compass. These two arm portions are hingedly secured together at their top and are operatively connected to the usual handle portion I2 as shown in Fig. 1. These ar-ms Ill and. II are of flat construction as shown in Fig.

and may be made of any suitable material such as Bakelite or like. The arm H has its outer marginal edge straight and marked as a ruler [3 as shown in Fig. 1. 0n the other side of the two arms l0 and II I have marked a protractor M as shown in Fig. 2. The numeral l5 designates the usual centering needle protruding from the lower end of the arm H.

The numeral i6 designates a longitudinal slot opening in the lower end portion of the arm Ill. The centralv portion of each of the walls of this slot is concave in cross section as shown in Fig. 3 to receive and partially embrace the lead ll. The numeral I8 designates a metallic handle sleeve having its two ends. pivoted 'by the rivet I9 extending through the lower portion of the arm [0 at one side of the slot l6 and with its central portion loosely embracing and extending around the opposite end portion of the arm 10 as shown in Fig. 3 and Fig. 4. The numeral 20 designates a cam slot in each side of the member I8. The numeral 2| designates a pin or like in each side of the arm I!) capable of being'engaged by the two cam slots 20 as shown in Fig. 3. These pins 2| are located in the end portion of the arm l0 opposite from that portion of the arm carrying the rivet 19. By this arrangement when the member I8 is manually moved outwardly and as shown in Fig. 4 the pins 2| will be free of the cam slots 20. When the sleeve lever I8 is moved effect the fiat character of the compass and eliminates necessity of knobs, screws, bolts and like usually found in compasses. When the memher I8 is in open condition, the lead ll may be manually slid inwardly or outwardly relative to the slot I5. After the lead has been properly adjusted, it is merel necessary to close the member l8, thereby tightly clamping the lead H in place.

Some changes may be made in the construction and arrangement of my improved substantially flat combination compass, ruler and protractor without departing from the real spirit and purpose of my invention, and it is my intention to cover by my claims any modified forms of structure or use of mechanical equivalents which may be reasonably included within their scope.

I claim:

1. In a device of the class described, two elongated arms each having a relatively large width relative to their thickness, a means for hingedly securing said two arms together, a pointed element'extending from the free end of one of said arms, a slot in the end of said other arm, a marking element slidably adjustably positioned within said slot, a handle member pivoted to said last mentioned arm and at one side of said slot, a circular cam slot in said handle member, and a projection on said last mentioned handle member capable of being engaged by said cam slot when said handle member is moved in one direction.

2, In a device of the type described including a leg member, a channel extending upwardly adjacent the lower end of said leg adapted to receive a marking element and adapted also to have the size of its cross section varied, a member pivotally mounted on said leg adjacent said channel, a cam slot in said pivotally mounted member and a protuberance on said leg adjacent said channel adapted to at times engage said cam slot to reduce the cross section of said channel.

3. In a device of the type described including a leg, a channel extending upwardly adjacent the lower end of said leg adapted to receive a writing element and adapted also to have the size of its cross section varied, a bifurcated member having the extended ends of its arms pivotally mounted on said leg to one side of said channel, protuberances on each side of said leg on the other side of said channel, cam slots in the arms of said bifurcated member adapted to engage said protuberances to reduce the cross section of said channel and means for manipulating said bifurcated member.

4. In a device of the type described a pair of leg members pivotally united adjacent their tops, a pointer element adjacent the lower end of one leg, a channel extending upwardly adjacent the lower end of the second leg, said channel being adapted to receive a writing element and capable of having the size of its cross section varied, a member pivotally mounted on said second leg adjacent said channel, a protuberance on said second leg adjacent said channel, and a cam slot in said pivoted member adapted to engage said protuberance to reduce the cross section of said channel.

EDWIN G. BROCKMAN. 

